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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?hpqLFi97yW6N/CyPnhVv0Onw8hFDXKflEiM3EQIxZ28OdeHbIvUiTmfH/JtY?= =?us-ascii?Q?Y6kEpx2ppAv1ZDx/OHSuFSEtNR2m0eZaVBV32IfbiG4OsY6rlGDL6olZ+oAk?= =?us-ascii?Q?OIirVCjnk+tVVZNPYxV8Dl7Q1pKv24+bXpydouDxcOjyGi+WuCoulcGulpWd?= =?us-ascii?Q?aLn1koSYuVrShCTcMwQKi3We2tEwfEkAn8daNu+ZoqbU4s5jWfcYelI84Apb?= =?us-ascii?Q?G+Y9gMir42VvXjj1KYl39qrdFEu6/OIzix1T43CvAwpQMeHEEJEMdAjYY1Yj?= =?us-ascii?Q?mvCZg/Io73cW7q9UKbtsBfJCluSkvVFcwR8vZzHe+SfoQgFyiy0HHc/r7oH4?= =?us-ascii?Q?s01Mf+hIYNw4tNi/dbL/VbVLXVBy2WvjHVM4yj+YuRozhG2xdtpYxaKp7cj1?= =?us-ascii?Q?OpkkhDaP1QoBEnov4g4w4p9EZoMfw/iPb5xlskY41w5hsjuay1XzdtQfTcFe?= =?us-ascii?Q?X2zXQHEc3VOCeuzVWbcOK6FpYXlg0nSkUXml8qH8e/yfniqPzHPOks9YBcoR?= =?us-ascii?Q?wKOty+PP6eIiXe5fkM/GKOWMXY6NgbAP0XIF1uNSvY/JlcnfnJoLlfFqkMCc?= =?us-ascii?Q?6qaOX8iDI8Q7HR8SFJMPrPbSeyPGzzYSb20cRQSzTQ2Q2OC1CNJYUhez2jqb?= =?us-ascii?Q?+FRAtfg9gAwjEZiT/LHtqknrDfiZMr7S8mKh1ORkcG6kGQd0NXD6DwO+pwiS?= =?us-ascii?Q?KreYpkZrw6PVb22aXoW8PTXvIdjdttLDR6mQdo8ZE+Aee9374xveFmI77dym?= =?us-ascii?Q?pfRJ2RIWF/dFtvvMsbncGtDz3f4jz5qz9KYXxXhCx++F6lttt0T2aGQxTQtO?= =?us-ascii?Q?juwJIUICa9oekwUiCpgDErDDBu97mRjqj0BoI/Afx2IdsWVQ8QIo1KvEIyjH?= =?us-ascii?Q?dxCw5tvQJHOH3Fcd80hkaBN1VyVYOG8iP0OkzdC7BqC04e4RmP2AQ8JjMHYS?= =?us-ascii?Q?eXk6MrrBeRwG4wRZuw0cNqAJoEqLe91ZzNVfGvGXCmOstJJm0DhYjIVs/9Np?= =?us-ascii?Q?tpuDbiC5g8L8JbheALNZFTim7qlmhEZSubjDfM3+dArJigy5GUi34cIWVPWS?= =?us-ascii?Q?MX1JRQctCMPSTqQyezoIBGdoO1pvArURi7RE48sO+tzY1k/lL/7MJZUj8ECp?= =?us-ascii?Q?ZKI+at4743uM8U62sFYCUjMI+WB7MiG79Ur7fWNiwcJsaWO3haPgLKsJJbXK?= =?us-ascii?Q?JNKmrhtUmLB+HZOPj355Sr9dUHOTv3Igr2g2hpiad2XLYtjPC28n4lkWv652?= =?us-ascii?Q?PwfyrxnzS/apREtg6e+k4nKodPhiJ5mtdhRpqSB3pwYBeZL9Hbx+BG/F9nU7?= =?us-ascii?Q?KRPivIu2seKc07UaA+nHd2w8uGSkXlkQBK3d1s2oaGkB7xOTv/NuWAz9SnUi?= =?us-ascii?Q?CAhJs7I6jpcNf/r1Uvvm48F4nkNzLPjtyZcdkMFA3w74D4e2wUqB0BOmS5OM?= =?us-ascii?Q?SPFnON/J1f9yrlqeQRxGqLSvibf5bc6bk/eauHW1cBuvbEQRI4PPHbv0yEl/?= =?us-ascii?Q?0KlumJWCZ5vCNGvOKMNYsX+E3R6lf61vfCCT7tcrOE7DplGZwdD1b+ZZkmYv?= =?us-ascii?Q?bRjNUYnA/RmXwOAaHsCR9KzQ32r89P9ylqA3Enwe?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 3db762e1-4111-4ded-979d-08dd994f19aa X-MS-Exchange-CrossTenant-AuthSource: BL4PR12MB9478.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 22 May 2025 16:38:38.0340 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 43083d15-7273-40c1-b7db-39efd9ccc17a X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: RK6XS1dysLylgu9S5m126OkszjWpovu8xJ28eksmGpxlodLFLYEv2p4HcKTBt4jE X-MS-Exchange-Transport-CrossTenantHeadersStamped: LV3PR12MB9258 On 22 May 2025, at 12:26, David Hildenbrand wrote: > On 22.05.25 18:24, Zi Yan wrote: >> On 22 May 2025, at 12:11, David Hildenbrand wrote: >> >>> On 21.05.25 10:02, Bharata B Rao wrote: >>>> Currently the folios identified as misplaced by the NUMA >>>> balancing sub-system are migrated one by one from the NUMA >>>> hint fault handler as and when they are identified as >>>> misplaced. >>>> >>>> Instead of such singe folio migrations, batch them and >>>> migrate them at once. >>>> >>>> Identified misplaced folios are isolated and stored in >>>> a per-task list. A new task_work is queued from task tick >>>> handler to migrate them in batches. Migration is done >>>> periodically or if pending number of isolated foios exceeds >>>> a threshold. >>> >>> That means that these pages are effectively unmovable for other purpo= ses (CMA, compaction, long-term pinning, whatever) until that list was dr= ained. >>> >>> Bad. >> >> Probably we can mark these pages and when others want to migrate the p= age, >> get_new_page() just looks at the page's target node and get a new page= from >> the target node. > > How do you envision that working when CMA needs to migrate this exact p= age to a different location? > > It cannot isolate it for migration because ... it's already isolated ..= =2E so it will give up. > > Marking might not be easy I assume ... I guess you mean we do not have any extra bit to indicate this page is is= olated, but it can be migrated. My point is that if this page is going to be migr= ated due to other reasons, like CMA, compaction, why not migrate it to the tar= get node instead of moving it around within the same node. -- Best Regards, Yan, Zi